运算 - df["C"]=df["A"]-df["B"]

import numpy as np
import pandas as pd
df = pd.DataFrame(data=[{"A":"1", "B":"3"}, {"A":"3", "B":"2"}, {"A":"2", "B":"1"}])  # 不可以字符串
df = pd.DataFrame(data=[{"A":1, "B":3}, {"A":3, "B":2}, {"A":2, "B":1}])

df["C"]=df["A"]-df["B"]
A列数据 减 B列数据 多了C列
df["C"]=(df["A"]-df["B"])*2
等等
df['time_long'] = (df['big_time'] - df['small_time']) / np.timedelta64(1, 'm')
时间datetime类型转为分钟